Electro-optical systems, also referred to as optically assisted electronics, perform certain operations in the optical domain and thus may have an enhanced overall performance. Such systems include optically realized low loss electrical delays, optically driven low phase noise oscillators, low loss interconnects, as well as mm-wave and THz signal generators. The high carrier frequency of optical signals when used in electrical systems enables electro-optical systems to have a performance that may exceed that of fully electrical systems. Furthermore, the relatively small size of some optical components, such as integrated photonic resonators, enable certain filtering operations to be performed in a smaller area compared to an equivalent fully electrical system.
In other electro-optical systems, such as low phase-noise optically-enabled mm-wave oscillators, the high optical carrier frequency enables design of high-Q electro-optical oscillators with phase noise levels approaching those of mm-wave designs with potential for relatively high tunability, and significantly lower size and power consumption. Delay lines limited by losses in the RF and mm-wave regime may be efficiently implemented in photonic integrated circuits. For example, an optical delay realized in a silicon-on-insulator (SOI) process may have over an order of magnitude less propagation loss than the same delay realized in a standard CMOS process.